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Itzchak Beiran

Publications and source records attributed to Itzchak Beiran.

13 recordsLinked to original sources
PubMed2006

Zinc-desferrioxamine reduces damage to lenses exposed to hyperbaric oxygen and has an ameliorative effect on catalase and Na, K-ATPase activities.

Our purpose was to investigate the effects of exposure to high partial pressure of oxygen on lens optical quality and on the activities of lenticular catalase and Na, K-ATPase in culture and to examine the effect of zinc-desferrioxamine (Zn-DFO) addition to cultured lenses exposed to high oxygen partial pressure on these parameters. Bovine lenses, kept in organ culture, were exposed to different combinations of partial pressure of oxygen with and without addition of Zn-DFO complex (20 microM) and examined during a 14-day period. Lens optical quality, catalase, and Na, K-ATPase activity were compared between study and control groups. Two hundred lenses were included in the present study. Decreased lenticular optical quality and decreased catalase and Na, K-ATPase activities were observed in lenses exposed to hyperbaric oxygen. Lenses exposed to normobaric oxygen showed a reduction in these parameters to a lesser degree. The damaging optical and enzymatic effects of oxygen on lenses in culture increased in magnitude along the culture period. Addition of Zn-DFO to the culture just before the exposure to hyperbaric oxygen eliminated most of the optical and enzymatic oxygen-induced damage. Addition of Zn-DFO after the first exposure demonstrated reduction in the oxidative damage induced reduction of optical quality in a time-dependent manner - the later the addition of Zn-DFO took place the smaller the protective effect observed. High oxygen load has toxic effects on bovine lenses in organ culture conditions as determined by optical parameters as well as reduction of catalase and Na, K-ATPase activities. These toxic effects can be attenuated by introducing Zn-DFO just before lenses are exposed to oxygen. The beneficial effect of Zn-DFO, applied after lenses have been exposed to hyperbaric oxygen, on the oxidative damage was time-dependent - the earlier the application the more significant the observed protective effect. The present results may indicate a possible future role for Zn-DFO as a protective agent against oxygen-induced human cataract formation.

Animals↗
PubMed2006

One medial triangular Tutoplast sling as a frontalis suspension for adult myogenic blepharoptosis.

PURPOSE: The treatment of choice for medium to severe blepharoptosis with minimal or no levator function is frontalis suspension with a sling, using a rectangular or rhomboid sling placement technique. We describe the short-term, follow-up results of frontalis suspension surgery for adult myogenic blepharoptosis using Tutoplast, a commercially available fascia lata allograft. METHODS: We conducted a consecutive, interventional case study. All adult (>25 years of age) patients operated for non-traumatic myogenic ptosis during a 1-year period were included. All underwent frontalis suspension using one medial triangular Tutoplast sling. Success was judged according to lid position and complications. RESULTS: Successful surgical results were judged by lid level, lid symmetry and lid contour. During a mean follow-up of 9 months, the success rate was 91% in all three criteria and 100% in at least two out of three. No major complications were observed. The most prevalent minor complication was the need for lubrication treatment in 26% of the operated patients. CONCLUSION: The use of Tutoplast for frontalis suspension in cases of adult myogenic ptosis is safe and has a high success rate in the early postoperative period. Further large-scale studies are necessary to ascertain the longterm results and the applicability of this material to other indications.

Adult↗
PubMed2005

[Upper lid frontalis suspension as a treatment for essential blepharospasm].

BACKGROUND: Essential blepharospasm is a progressive disease of unknown etiology causing a significant decline in the quality of life of patients suffering from the disease. Currently used treatment for this condition is repeated injections of Botulinum toxin. Some of the patients' therapeutic response to Botox injections is insufficient, and some develop ocular complications. GOALS AND METHODS: This report presents our experience with sling frontalis suspension for essential blepharospasm in 4 patients with follow-up periods of six months to 2 years. A literature review is presented and discussed. RESULTS: A treatment trial with Botox injections was attempted in all four patients. Three of the patients showed insufficient treatment response. Three of the patients developed side effects of recurrent episodes of upper lid ptosis following injections. In all four patients that underwent operations significant reduction of blepharospasm was observed. In two of the patients Botulinum toxin could be discontinued, in one patient treatment intensity could be reduced, and in three--treatment complications were prevented. All four patients reported a high degree of satisfaction from treatment results. CONCLUSIONS: Our results indicate that sling frontalis suspension for essential blepharospasm is a safe and efficient treatment for essential blephrospasm with a high degree of patient satisfaction. Further large-scale studies are needed to substantiate our results.

Aged↗
PubMed2005

[Oxygen effect on ocular lens].

BACKGROUND: Cataract is the leading cause of preventable blindness worldwide. Clinical observations and laboratory results have shown that oxygen has a possible toxic role in cataract formation. AIM: The aim of the present study was to demonstrate, measure and characterize the damage caused to bovine lenses in organ culture as a result of their exposure to hyperbaric oxygen pressure. MATERIALS AND METHODS: Twenty bovine lenses exposed to hyperbaric pressure were compared to 20 control lenses. Lenses were kept in an organ culture for 14 days. Each day the focusing ability of the exposed lenses was compared to controls. The comparison was based on the amount to which the focus point of each measured ray diverged from the focus point of the lens. Lenses were also examined under the microscope and morphologic changes in study lenses were compared to controls. RESULTS: A statistically significant difference in focusing ability between the study and control lenses was observed. The difference became larger during the incubation period indicating an accumulation of damage. The damage resulted from the peripheral but not the central part of the lenses. The morphologic changes observed under the microscope matched the damage profile of the focusing ability. CONCLUSIONS: Oxygen has a possible role in cataract formation. The effect of oxygen is cumulative. The route of damage formation follows the diffusion of oxygen into the lens.

Animals↗
PubMed2003

Haptoglobin phenotype in age-related macular degeneration patients.

PURPOSE: To investigate a possible role of the haptoglobin phenotype in the development of exudative age-related macular degeneration (AMD) in human subjects. DESIGN: Prospective, observational, comparative population study. METHODS: The study was carried out in an institutional setting. All patients referred because of exudative AMD in one eye during an 18-month period were included in the study group. A group of patients treated for other ocular diseases and not having AMD in either eye served as control. Haptoglobin phenotype was determined from a blood sample drawn from each patient in both the study and control groups. The main outcome measure was the distribution of the haptoglobin phenotype in the study and control group. RESULTS: One hundred eighty-five participants were included in the study. Ninety-eight had exudative AMD, and 87 were AMD-free. The difference between the study and control groups in distribution of the haptoglobin phenotype was found to be statistically insignificant. CONCLUSIONS: Our results suggest that the haptoglobin phenotype has no effect on the prevalence of exudative AMD.

Aged↗
PubMed2003

Posterior lamellar gold-weight extrusion.

We report a case of a man who had undergone gold eyelid loading for lagophthalmos 22 years earlier. During examination for a complaint of foreign body sensation in the operated eye, the gold weight was found under the palpebral conjunctiva. Although extrusion of a gold weight through the skin anteriorly is well recognized, posterior extrusion has not been previously reported. Although such an extrusion involves tarsal plate erosion, the patient's complaints in this case were minor, probably due to the chronic nature of the process. This finding should serve to draw the attention of surgeons using gold eyelid loading to the possible, albeit rare, complication of posterior extrusion.

Eyelid Diseases↗
PubMed2003

Lenticular oxygen toxicity.

PURPOSE: To investigate the possible toxic effect of oxygen on lenses in an organ culture. METHODS: Bovine lenses were exposed to four different combinations of ambient pressure and oxygen concentration in an organ culture throughout a 7-day period. Lens transparency, histology, enzymatic activities, and photomicrographs were compared in study and control groups. RESULTS: No differences were observed between study and control lenses in all measured parameters in a group subjected to a single exposure of 100% oxygen under increased (i.e., hyperbaric) ambient conditions and a group exposed repeatedly to high ambient pressure and normal oxygen partial pressure. Decreased lenticular transparency and enzymatic activities along with structural changes were observed in lenses exposed repeatedly to 100% oxygen concentration under both normal and increased ambient pressures. The observed changes were oxygen-load-dependent: the higher the oxygen partial pressure and the longer the time of exposure, the more severe the changes observed. Optical and structural changes in the lens occurred in a centripetal orientation: the greater the oxygen load, the more central the damage. CONCLUSIONS: High oxygen load has a toxic effect on bovine lenses in organ culture. These effects appear to be cumulative: the higher the oxygen partial pressure and the greater the number of exposures, the more severe the changes observed in the lenses. Changes marking toxicity follow the route of oxygen diffusion into the lens, from the periphery to the center. Cautious interpretation of the results may indicate a role of oxygen (and/or its derivatives) in human cataract formation.

Animals↗
PubMed2003

[Presumed Candida tropicalis endophthalmitis following anterior resection].

We present a case of a 75 years old patient who developed a presumed Candida Tropicalis endophthalmitis after an anterior resection for rectal carcinoma. The pathogen was identified in blood cultures but not in vitreal cultures. Systemic anti fungal treatment brought no ocular improvement. After having a vitrectomy and intravitreal antifungal agent injection gradual improvement up to full resolution took place. To the best of our knowledge, this is the first report of a post surgical candida tropicalis endophthalmitis in a non-neutropenic patient. We suggest special attention to ophthalmic complaints in patients with systemic candidemia and prompt treatment according to ocular findings.

Aged↗
PubMed2002

Acetazolamide for central serous retinopathy.

OBJECTIVE: To find out whether acetazolamide has a beneficial effect in the treatment of central serous retinopathy (CSR). DESIGN: Prospective, nonrandomized, comparative trial. PARTICIPANTS: Fifteen acetazolamide-treated and 7 untreated (control) CSR patients who completed at least 24 months of follow-up. METHODS: Patients in the treatment group were given systemic acetazolamide according to a standard protocol. Main outcome measures were compared between treatment and control groups using Student's t test and the Mann-Whitney U test for statistical analysis. MAIN OUTCOME MEASURES: Time until subjective visual improvement, time until full clinical resolution, and rate of recurrences. RESULTS: Mean times to both subjective visual improvement and clinical resolution of the attack were shorter in the study group than in the control group. Recurrence rate did not differ between the study and control groups. CONCLUSIONS: Acetazolamide treatment for CSR shortens the time for subjective and objective clinical resolution, but has no effect on either final visual acuity or recurrence rate of the disease.

Acetazolamide↗
PubMed2002

Characteristics and functional outcome of traumatic hyphema without routine administration of epsilon-aminocaproic acid.

BACKGROUND: The prevalence of traumatic hyphema as well as the distribution of its severity varies among different patient populations. Treatment recommendations in the literature differ significantly among various published reports. This lack of a uniformly accepted treatment probably reflects the different characteristics of this pathology among the populations investigated and cells for a population-adjusted treatment recommendation. OBJECTIVES: To report the characteristics and functional outcome of patients with traumatic hyphema and to discuss possible recommendations regarding the use of epsilon-aminocaproic acid. METHODS: A prospective, non-randomized study was conducted in 154 consecutive patients with traumatic hyphema, including data collection of ophthalmic status at various time points, the presence or absence of secondary hemorrhage, and final visual acuity. RESULTS: Of the 154 eyes studied over 3 years, nearly 90% had hyphema of grade 1 or less, 5 (3.25%) experienced rebleeding, and 2 (1.3%)--neither of which rebled--needed surgical intervention. None of the four patients who experienced final visual acuity of 6/40 or less suffered rebleeding. CONCLUSION: The use of epsilon-aminocaproic acid in the studied population was unjustified and routine use of epsilon-aminocaproic acid in our patient population is probably not indicated. A treatment policy regarding epsilon-aminocaproic acid use should be adjusted to the population being treated.

Adolescent↗